Firearm.



PATENTED OCT. 1'7, 1905.

R. FROMMER.

FIREARM.

APPLICATION FILED FEB.13,1902.

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PIREARM.

APPLIOATION FILED H1313, 1902.

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PIREARM.

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No. 802,279. PATENTBD OCT. 1v7, 1905.

R. FROMMER.

FIREARM.

APELIOATION FILED PBB.13,1902.

5 SHEETS-SHEET 5.

' "UNITED STATES PATENT OFFIOE.

FIREARIVI.

Specification of Letters Patent.

Patented Oct. 17, 1905.

Application filed February 13, 1902. Serial No. 93,823.

To all whom, it wtay concern.-

Beit known that I, RUDOLF FROMMER, a citizen of the Empire ofAustria-Hungary, residing at IX Soroksari t 100, Budapest, Austria-Hungary, have invented certain new and useful Improvements in Firearms;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, suoli as will enable others skilled in theart to which it appertains to make and use the same.

The present invention relates to firearms, and is designed to provide anautomatic firearm distinguished from those of former construction by thespecial simplicity, compactness and accessibility of all its parts, andthe easy manner in which it can be put together and taken to pieces.

With these objects in view my invention consists in the features, means,and combinations of parts, as hereinafter described and-as particularlypointed out in the claims hereunto annexed. Y

Two forms of construction of a firearm made according to this inventionand constituting the preferred embodiment thereof are illustrated in theaccompanying drawings, in which Figures 1 to 14 show it as va firearmadapted for use as apistol, and Figs. 15 to 19 asa shoulder-firearm.

Fig. 1 is a central vertical longitudinal section of the first form ofconstruction. Fig. 2 is a horizontal section on the line A B of Fig. 1.Fig. 3 is a` vertical longitudinal section of the same when open afterthe last cartridge has been fired or with empty magazine.

Fig. 4 is a vertical longitudinal section showing how in the same kindof firearm after the last cartridge has been fired the breech mechanismrigidly connected with the barrel and breech chamber arrives.' (togetherwith the latter parts) by means ofthe recoil in its rearmost positionand how the breech after firing the last shot is automatically kept openextractor.

Figs. 5 to 14 are details of the samev Fig. 11 is a vertical section ofthe breech-chamber on the line C D of Fig. 1'. Fig. 12 is an elevationof the feed-plate. Fig. 13 is an elevation of the detent-lever. Fig. 15is a vertical longitudinal section of a shoulder-firearm also embodyingmy invention. Fig. 16 is a section on the line A Bl of Fig. 15. Fig. 17is a vertical longitudinal section of the firearm before the lastcartridge is introduced into the charg'e-chamber. Fig. 18 illustratesthe arrangement of the detent, the bolt-catch, and the sear. Fig. 19 isa vertical section of the ring-pin from behind the firing-pin catch.Fig. 2O is a vertical section of the breech-chamber and the breech-boltand a back view of the tumbler and the detent. Fig. 21 is a sideelevation of the parts shown in Fig. 20, and Fig. 22 is a plan view y ofthe tumbler and detent.

, The barrel 1, Fig. 1, and the barrel extension 2, which is made in onepiece with or screwed onto the barrel, are adjustably placed in suitableguides of the frame 3. An annular groove 2b, Fig. 3, is made in thebarrel extension 2, which groove is connected with aseries oflongitudinal rearwardly-opening grooves 2, Figs. 3 and 11. The holt 4 ispushed into the barrel extension 2 and is coupled with the breech-block5 by means of the arrangement, Fig. 6, of suitably-placed ribs 4i on thebolt 4, which engage in spiral grooves 5l of the breech-block 5. Owingto this arrangement, the breech-block 5 has to revolve on itslongitudinal axis in the bolt with each displacement.

If now during the forward movement in a straight line of thebreech-block 5 (coupled, by means of the spiral grooves and ribs, withthe bolt 4) the studs 5a on the breech-block have passed the grooves 2,the breech-block 5 strikes against the front face of the annular groove2b and is thus checked in its movement forward; but the bolt 4 is stilldriven forward under the action of the spring 10, and by means of thisrelative motion of the two parts, owing to their connection by spiralgrooves and ribs, the breech-block 5 revolves on its longitudinal axis,whereby the studs 5a firmly rest against the rear end of the annulargroove 2bbetween the grooves 2c, and the breech is rigidlylocked. Thefiring-pin 8 passes through the breech-block 5, Fig. 1, and through theplate 6, which is fixed in the frame 3 .by means of the screw-bolt 7.The firing-pin is normally held in retracted position by means of thespring 9.

Ioo

IIO

Of the springs 10 and 11 the former (one end of which rests against ashoulder within the bolt 4 and the other end against the plate 6)operates the breech mechanism, while the latter 11 (which with its rearend rests against a shoulder of the frame 3 and with its front endagainst the barrel-sleeve 12) serves for bringing back the barrel 1 andthe barrel extension 2 into the position they were in before the recoil.As it is of great importancethat the barrel-sleeve 12, which forms thestop for the barrel-spring 11, should be connected in anabsolutely-reliable manner with the barrel 1, the barrel-sleeve 12, Fig.7, which is provided with a bayonet-groove and placed on the boss 1l ofthe barrel, is furthermore secured by a nut 13, both of which, as shown,engage within one another at one or more places by interlockingtenon-and-mortisc connections in the manner of a clutch-coupling. lInorder to obtain an absolutely secure joint with the barrel, thedirection of rotation of the bayonet-groove is contrary to that of thethreading ofthe nut 13. For instance, if the bayonet-joint is to turn tothe right then the nut 13 has a left-hand screw-threading, and viceversa. 1t is thus obvious that the nut 13 cannot come oii' thebarrel-sleeve 12 by accident; but even if it should the bayonet-jointalone would insure a secure connection between the barrel-sleeve 12 andbarrel 1. In order to remove the barrel-sleeve 12, as well as the nut13, the barrelsleeve must be pressed against the barrel-spring 1l, whenthe rib and groove of the lmrrel-sleeve and the nut will come out ofengagement. The nut 13 can then be unscrewed and the barrel-sleeve l2twisted out of the stud 12 The ejector 14, Fig. 2, is inserted in thebarrel extension 2, and preferably under spring force, while thecartridge-extractor 15, Fig. 9, is embedded in the breech-block andengages with its projection 15, Fig. l0, in a corresponding notch in thetiring-pin 8 in order to prevent the latter falling out backward.

The trigger 16, pivoted on the triggeipin 17, forming one piece with theframe 3, is controlled by the trigger-spring 18 and has a catch 20controlled by a spring 19,` which catch is arranged to swing on thepivot 2l. The sear 22 is pivoted on the pin 23 of the frame and iscontrolled by the Sear-spring 24, which constantly presses it againstthe hammer 25. This latter is pivoted on the pin 26 of the frame and iscontrolled by the main` spring 28, coiled round the forcing-bolt 27'.4

The hammer 25 is limited in its swinging motion by the mantle 3 at 31.

The tumbler 29, Fig. l, is pivoted on the piu 30 of the frame and isconstantly pressed upward by the spring 3l. The back part of the tumbler29 is in the form of a segmental are concentric with the pin 30, and ithas also a lateral reinforcen'ient with oblique contact-Y surface, asshown in the dotted line 29. Also pivoted on the pin 3() is the detent32, Fig. 3, (not shown in Fig. 1,) which is controlled by a spring 33,which is embedded in a suitable underflap 29b of the tumbler 29.

One operative edge ofthe detent 32 is formed with a sloping end 32,while the other is formed as a catch at 32". The sloping edge 32 engagesin the notch 4, Figs. 5, .5, and 6. with every backward motion of thebolt 4, but is again pressed down by the inclined rear end of the notch4" of the bolt when the bolt moves forward, as long as the detent-lever35, Fig. 3, does not come into engagement with the catch 32]. On thebolt 34, forming one piece with the frame which passes through an ovalaperture 16 of the trigger, Fig. 1, is pivoted the detent-lever 35, thedownward movement of which is limited at 3, Fig. 3, by the frame. Themagazine 36 contains the feedspring 37 and the feed-plate 38, which isillustrated in Figs. 8 and 14 in its coperation with the detent-lever35.

It will be seen from Fig. 12 that the feedplate 38, which is inside themagazine 36, has a lateral tailpiece 38, which projects through the slotof the magazine and is reinforced outwardly by a shoulder at 38, whileit will be seen from Fig. 13 that the detentdever 35 is reinforcedinwardly by a shoulder, as shown by thedotted line. These tworeinforcements come into engagement with each other (see Figs. 8 and 14)when the feed-plate 38, controlled b'y the feed-spring 37, goes up asthe magazine empties. Consequently the detentlever 35 is also lifted upas the magazine 36 is about to be emptied. The tooth 35" of thedetent-lever is hereby caused to make an arcshaped movementaround thebolt 34, thereby coming under the lower edge of the tailpiece 38" of thefeedplate 38, and so that when the feed-plate 38 is pressed down thedetent-lever 35 is likewise pressed down. rl`he feed-plate 38 can alsobe pressed down by pressing downward theknob 35h of the detent-lever 35.

ln the T-groove 3" of the frame 3, Figs. 1, 3, and 4, is movablyarranged the safety device 39, Figs. 3 and 4. The latter has threeprojections 39 39b 39, Fig. 4, of which one, 39, stops the action of thedetent 32 and the others that of the scar 22 and the hammer 25,respectively, according as the safety-piece 39 by being moved forward,Fig. 4, or backward, Fig. 3, is put out of or into action. A flat spring52, Fig. l, serves to retain the safetypiece in its operative orinoperative position and is arranged in a groove cut in the frame at 3cand extending into the T-groove 3". r1 he knurled button 39 of thesafety-piece 39, as well as" the knurled button 35" of the detentlever35, project through suitable apertures in the frame. When the bolt 4 isin its forward closed position, (asin Fig. 1,) the sloping end 32 of thedetent 32 engages in the notch 4, Fig. 3, of the bolt 4. When this issecured IOC) ITO

and the safety-slide moved back, the upper projection 39 ofthesafety-piece 39 engages under the .downwardly-bent projection 32c ofthe detent 32, and thereby the bolt 4, and therefore all the parts whichare movable rearward, (breech-block 5, barrel 1, barrel extension 2,)are immovably fixed. The sear 22 (at 22u) and the hammer 25 (whethercocked at 25a or at half-cock at 25h) are also fixed by the two lowerprojections 39b and .39 of the safety-piece 39. Consequently the movableparts, as well as the trigger mechanism, are made safe.

The method of operation of the firearm is as follows: At the moment offiring the barrel 1, the barrel extension 2, and the whole breechmechanism are thrown back by the recoil, Fig. 4, whereby thebarrel-spring 11, the spring 10, the hammer 25, and consequently themain spring 28, are set. The tumbler 29 thereby comes into engagementwith the notch 4a (see Figs. 1, 5, 5, and 6) of the bolt and fixes thebolt and the whole breech mechanism in its rearward position. The forceof the recoil then immediately ceases, and the barrel 1 and the barrelextension 2 are again driven forward by the barrel-spring l1. rfhebarrel ex- I tension 2 takes with it the breech-block 5, consequentlydrawing it out of the bolt 4, Figs. 3 and 6, whereby the breech-blocktwists round until the studs 5 pass into the grooves 2c or into thecross-head guides in the barrel extension 2, forming continuationsthereof. As the barrel l and barrel extension 2 are now driven forwardby the barrel-spring' l1 and the empty cartridge-case, firmly held bythe cartridgeextractor, is thrown out by the ejector 14, Fig. 2,arranged in the barrel extension 2 and operating in the well-knownmanner, thebreech mechanism remains fixed in its rearward position bymeans of the tumber 29 until the sloping edge 2 of the breech, Figs. 1,15, and 17, reaches the sloped raised surface 29u of the tumbler' 29,whereby the latter is pressed down, the'mainspring 10 can come intooperation and drive forward the breech mechanism, which pushes into thecharge-chamber the fresh cartridge, (which has meanwhile been raisedfrom the magazine,) whereby the studs 5 of the breech-block, which havepassed into the grooves 2, Fig. ll, in the annular groove 2b turn in thesaid groove and become firmly locked with the barrel extension 2. Thearm is now ready for firingwthat is, cocked-rigidly closed and charged,and can again be fired off by pulling the trigger, and theabove-described operation is repeated as long as there is ammunition inthe magazine.

1n order t'o insure that the hammer 25 is held securely by the sear I22after every shot, so that there may never be more than one shot eachtime the trigger 16 is pulled, there is a catch 2O pivoted on thetrigger and which when the trigger is pulled comes into engagement withthe sear 22 and lifts the latter only to the intersecting-point of thearcs of two circles, (the pivots 17 and 23 being taken as centers,)whereupon the sear 22, actuated by the spring 24, springs off theprojection 2O at the moment when the notch of the hammer 25 is releasedfrom the nose of the sear 22, the hammer being consequently released.The Sear 22, however, at the same moment being releasedfrom the triggeris returned to its operative position by means of' the spring 24 andremains ready to again hold the hammer 25, which will be driven back bythe recoil. The arrangement of' the projection 20 being such that thesame is held rigidly against movement in one direction enables thetriggerv 16 to return to its original position without thereby affectingthe sear 22.

In order that the firearm after the last eartridge has been fired mayremain open and ready for recharging, it is so arranged that afterfiring the last cartridge, Fig. 3, the de- "tent-lever 35 is broughtinto engagement with the projection 32b of the detent 32 by means of thefeed-plate 38.

The detent 32, which with every backward motion of the bolt`4 passesinto its notch 4b, Fig. 5, but is pressed down on its sloping part 32aby the slope of this notch, owing to the action of the spring 10 forcingthe bolt 4 forward, must now remain in its upper position, owing to theengagement of the detent-lever 35 in the projection 32h, andconsequently retains the breech mechanism in its rearward position untilby inserting fresh ammunition or by pressing on the knurled button 35hofV the detent-lever 35 the feed-plate 38 is pressed down. Until thebreech mechanism is closed the lugs 4d of the bolt prevent the forwardmotion of the hammer 25 even if the trigger is pulled.

The second form of construction of the automatic firearm forming thesubject of this inven` tion is in essentials the same as that describedabove, except that the hammer is in this instance replaced by afiring-pin. Figs. 15 to 19 of the drawings illustrate thosemodifications required by the omission of the hammer and thesubstitution therefor of a firing-pin 41, controlled by the mainspring40. 1n this form, Fig. v17, 42 is the bolt-catch, which in this caseperforms the function of the tumbler 29,Fig.1; 43 the sear, whichengages with the catch 44 of the firing-pin, and 32 the detent, whichafter firing the last shot is rigidly held by the projection 38c of thefeed-plate in the corresponding notch of the bolt 4 and keeps the breechopen until freslr ammunition is supplied or the feed-plate 38 is presseddown. The operation of' the trigger mechanism is substantially the sameunder this construction as in the construction iirst described, only inthe present case the movable4 catch 2O instead of being mounted directlyon the trigger 16 is arranged on a separate lever 53, yieldinglyactuated by a spring 54. This trip-lever 53 is actuated by the trigger16 when the latter is pressed in TOO IIO

The indicator 3. `lin automatic guns a recoil-barrel, and a magazineprovlded with a feed-plate, in com- 47, Figs. and 1T, I shows whetherthe lirei bination with asliding breech-bolt, a tumbler,

arm is cocked or not. the pin 47, pressed forward by the spring 48,remains invisible, as this spring can only be overcome by the action ofthe compressed mainspring L10, Figs. 15 and 17. Thetensions of these twosprings are so adjusted relatively that the pin 47 is forced rearwardwhen the mainspring is compressed suiiiciently to cock the firearm-thatis to say, to cause the catch 44 ot' the iiring-pin to be engaged b vthe sear 43 when the indicator becomes visible. The safety device 49 isconstructed as an eccentric which can bear at 50 on the trigger orrelease the same.

Fig. 1S shows the lateral arrangement of the detent 3Q, the bolt-catch42, and the scar 43. Of course the bolt 4: is suitably slotted, as shownat 1b. on account oi' the catch 44 of the tiring-pin.

The method ot' operation of the shoulderfirearm is the same as that ofthe hand-arm. At the momentotl firing, the barrel 1, the barrelextension 2, and the whole breech mechanism are driven back by therecoil, whereby the barrel-spring l1, the closing-spring 10, and theniainspring 4() are compressed. The bolt-catch @LQ thereby comes intoengagement ith a notch (identical with the notch t in ig. 1) in the holti and fixes the bolt, and consequently the whole breech mechanism, inits rearward position, Fig. 17. lhe liring-pin is stopped by the scar13, which has come into engagement with the catch #if-L. The forwardmotion ot' the barrel and the opening of the breech effected thereby, asalso the ejection of the cartridge-case and the charging and closing ofthe breech after the release of the bolt-catch 4Q by the sloping edge 2"of the barrel extension, are ei'ected in exactly the same manner as withthe hand-firearm described above in detail.

fluit I claim, and desire to secure by Letters Patent of the UnitedStates. isM

1. In automatic guns a recoil barrel a breech-bolt and a xnagazineprovided with a feed-plate in combination with a detent device for thebreech-bolt adapted to be released by the advance et' the breech-boltand a detent-lever, as 35, connected with the feedplate and adapted tobear against a projection n the detent to lock it against release whenhe magazine has been emptied and the feedplate has reached the upperpart of the same.

2. In automatic guns a recoilbarrel a reech-bolt and a magazine providedwith a feed-plate in combination with a detent dciee for the breech-boltadapted to be released by the advance of the breech-bolt the feed- )latebeing so arranged as to bear against the ietent and lock it againstrelease when said eed-plate has reached the upper part of the agazine.

Thisisarrangedso that l and a detent, shoulders on the breech-boltadapted to be engaged by the tumbler and detent, means for releasing thetumbler when the barrel reaches the tiring position, an inclined facefor releasing the detent as the bolt advances, and means operated by thefeedplate for locking the detent against release when the feed-plate ofthe magazine reaches a predetermined position.

4. In automatic guns, a recoil barrel, a magazine provided with afeed-plate, in combination with a sliding bolt, a tumbler, and a detent,notches on the breech-bolt to be engaged by the tumbler and the detent,a slopl and a detent, notches on the breech-boltadapted to be engaged bythe tumbler and thedetent, a sloping edge on the breech-chamber adaptedto release the tumbler when the barrel reaches the iiring position, asloping edge on the breech-bolt adapted to release the detent when thebreech-bolt advances, and means controlled by the feed-plate and soarranged as to bear against the detentand lock itagainst release whensaid feed-plate has reached the upper part of the magazine.

i 6. ln automatic guns a recoil-barrel and a .spring for thrusting itforward, in combination with a barrel-nut and a barrel-sleeve jforretaining the spring mounted on the barrel, interlocking meansconnecting the barrel-nut and the barrel-sleeve and means for securingthe barrel-sleeve in position on the barrel, the barrel-sleeve being soarranged that to release the same it is necessary to turn in a directionopposite to the direction to unscrew the barrel-nut.

7. ln a gun, a recoil-barrel, and a spring for thrusting' it forward, incombination with a barrel -sleevc for retaining the spring and mountedon the barrel, and means for securing the same in position consisting oia bayonet-joint providing for longitudinal movement between the parts ina coupled position, a barrel-nut and interlocking means connecting thebarrel-n utand the barrel-sleeve, the means for releasing the barrel-nutfrom the barrel operating in a direction opposite to the means forreleasing the barrel-sleeve.

8. ln a gun a recoil-barrel, and aspring for IOO IIO

thrusting it forward, in combination with va barrel-sleevebayonet-jointed to the barrel in such manner as to provide for a limitedrelative longitudinal movement of the parts' in their coupled positionand a barrel-nut threaded on the end of the barrel and connected withthe barrel-sleeve by a clutch-coupling, the bayonet-joint on the sleeveand the thread on the barrel-nut being so arranged as to turn inopposite directions on being released.

9, In automatic guns, a magazine feed-plate having a laterally-extendingshoulder, in combination with a detent for lockingV the breechbolt inits open position, a detent-lever pivoted to one side ot' the path ofthe feed-plate, a shoulder on the lever arranged to be en' gaged bytheshoulder of the feed-plate in the upward movement of the latter, and atooth projecting from the lever arranged to clear the feed-plateshoulder in its upward movement and to be engaged thereby in itsdownward movement whereby a depression of the feed-plate will operate to'positively depress the detent-lever.

10. In an automatic gun, a cock, a sear for the same, and a detent forthe breech-bolt, in combination with a safety-piece mounted for movementinto and out of engagement with the cock, sear and detent.

11. In va gun, an indicator engaging a slot in the same and a spring forretracting the same into the firearm, in combination with a firing-pinand a spring arranged between the firing-pin and the indicator, the twosprings being of such relative strength that in compressing the latterby retracting the firingpin, the indicator is thrust out of the firearm.

In testimony whereof I aiix my signature in presence of two witnesses.`

RUDOLF FROMMER.

Witnesses:

' FRANK DYER CHESTER,

SCHN FRosz.

